code: def test_statefulness_single_state(self):
      sequence = np.ones((1, 2, 3))
      layer = layers.RNN(OneStateRNNCell(2), stateful=True)
      layer(sequence)
      output = layer(sequence)
      self.assertAllClose(np.array([[45.0, 45.0]]), output)
  
      layer = layers.RNN(
          OneStateRNNCell(2), stateful=True, return_state=True
      )
      layer(sequence)
      output, state = layer(sequence)
      self.assertAllClose(np.array([[45.0, 45.0]]), output)
      self.assertAllClose(np.array([[45.0, 45.0]]), state)
  
imports: import numpy
  import pytest
  from keras import layers
  from keras import ops
  from keras import testing
label_desc: Use image node_id 9 for calling the RNNTest obj's underlying member method code with example usage: obj.test_statefulness_single_state() without return types